TD Garden officials are investigating after a fire alarm went off Wednesday night, triggering an evacuation of the arena about an hour after the Boston Celtics playoff game against the New York Knicks, officials said. “The cause of the fire alarm is currently under investigation,” according to a TD Garden statement Thursday.

Post-game activities came to an abrupt, and alarming end at the TD Garden Wednesday following the Celtics loss to the Knicks in Game 2 of the NBA playoffs, when the building was evacuated as fire

TD Garden officials had to evacuate people out of the building due to an emergency after the Celtics' Game 2 loss to the Knicks.